A dulcarnon used to mean a difficult or impossible puzzle. But where that came from is quite a story.
Chaucer wrote more than just The Canterbury Tales, and some of his other works are nearly as famous. He wrote “Troilus and Criseyde” around 1385 or so, for example. It’s a long poem that retells the story of Trolius and Criseyde, two lovers during the Siege of Troy. The Trojan War is a story from ancient Greek mythology, of course, and nobody is quite sure whether it really happened. In fact until fairly recently most people thought “Troy” had never been a real city, but archeologists suggest that it probably was real — and is now Hissarlik, a city in Turkey. (The “Hissarlikean War” doesn’t really have the same ring to it, though.)
Anyway, back to Chaucer, and “Troilus and Criseyde.” He actually finished it, unlike the Canterbury Tales, and people who actually enjoy reading things written in Middle English (an irritating experience for everybody else) think it’s the better piece of writing. It’s even contributed to the language we use today; it’s the source of the phrase “all good things must come to an end.”
But it’s also the source of this: “I am, till God me better mindè send, / At dulcarnon, right at my wittès end.” That’s Crisyde complaining that she’s “at dulcarnon.” It’s in Book III (out of five), and you have to go to the unabbreviated version to find it. It is available online though, with Middle English spelling corrected to more or less modern practice (don’t ask me how Middle English can have modern spelling). But “dulcarnon” was an unusual word even for 1385. It was so unusual that for 500 years nobody had any idea what it meant or where it came from. But Walter Skeat, who coincidentally was born in 1835, the 500th anniversary of Chaucer’s poem, grew up to be a leading philologist (a combination of literary critic, historian, and linguist; philologists are always the life of any party). He was also a Chaucer scholar, and he’s the one who figured out what “dulcarnon” meant. It comes from the Arabic word “dhu’lqarnayn,” which means “two-horned,” like a goat.
It seems that Alexander the Great (or Alexander the Third) was the king of Macedon, in Greece, around 330 BCE. Instead of sitting at home on his throne he set off with his army into Asia and Africa and created an empire that stretched from Greece to India. When he was a boy his tutor was Aristotle himself. And that part is important, because Aristotle was the leading man in spreading the ideas of his own tutor, Plato. And Plato was greatly influenced by Pythagoras, the guy who invented that theorem about right triangles; “the square of the hypotenuse is equal to the sum of the squares of the other two sides.”
The most common way to illustrate the Pythagorean Theorem (and the way Euclid showed it in his original “Elements of Geometry” textbook, which was your only choice in those days) is to draw a right triangle with the longest line on the bottom (that’s the hypotenuse), and the two other lines at angles above it — and then you draw squares off of each of the three sides. When you do that, you get a big square on the bottom and two smaller ones at angles on the top. If you look at it just right it looks a little bit like a face with horns on the top. You have to squint your eyes — okay, it works best if you just assume that centuries ago people might have been pretty bored and dreamed up this “oh it looks like a head with horns” story.
Now, Plato knew the Pythagorean Theorem, and taught it to Aristotle, who taught it to Alexander. Alexander was more interested in fighting wars (which he always won) and building his personal brand than philosophy or geometry, and it’s quite possible he, like many, many other people back then (or, possibly, even now) had great difficulty understanding or caring what on earth Pythagorus had been talking about. So he ignored it and worked on other things like sharpening his sword and claiming that he was descended from the Egyptian god Amun. Amun, like most Egyptian gods, was depicted as a combination of human and animal — in this case, a ram. That is, Amun had ram’s horns on top of his head.
The story about Alexander being descended from an Egyptian god turned out to strike a chord with folks back then, for some reason. It doesn’t make much sense, seeing that Alexander wasn’t even Egyptian, but anyway, it stuck. And that’s important because in Arabia people began to call him “dhu’lqarnayn,” or “two-horned”. When they saw the illustration of the Pythagorean Theorem, they thought two things. One was that it reminded them of a horned head, like the one Alexander the Great didn’t have (but he was always at the top of the news anyway so people were thinking about him). The other was that this geometry stuff was really hard and they didn’t get it. So “dhu’lqarnayn” came to mean a very difficult or even impossible puzzle.
Now back to Chaucer. In his poem, Criseyde knew that a “dulcarnon” was an impossible puzzle because her uncle Pandarus explained what it was to her. He told her a “dulcarnon” was also called the “flight of wretches”. But being a writer instead of a geometrician, Chaucer actually got that wrong! There IS a proposition in geometry that back then was called the “flight of wretches”, but it’s not the Pythagorean Theorem. Instead it’s the one about an isosceles triangle (the one with two equal sides) that shows that the angles opposite the equal sides are also equal.
So the whole thing was a bit of a mess, and you might still be a bit confused about why Alexander the Great is involved in this story at all. The answer lies in the work of Walter Skeat. He was a philologist, as you’ll recall. A linguist AND a historian. And the way he was able to finally figure out what Chaucer meant by “dulcarnon” was because he found it mentioned in ancient references to Alexander. Who probably wasn’t much better at geometry than Chaucer was.
